ADHD symptoms have been previously identified as key risk factors for internet gaming disorder (IGD); however, the effect on the longitudinal course of IGD remains to be elucidated. This study aimed to determine whether ADHD comorbidity in individuals with IGD affects recovery, recurrence rates and trajectories of IGD symptoms.
This study was part of a cohort named ‘problematic gaming group’, which has the goal of exploring clinical and neural outcomes related to IGD and comorbid psychiatric disorders. Outpatients from the psychiatric clinics of Chung-Ang University Hospital, Seoul, Korea were recruited to the study.* IGD and ADHD were diagnosed according to Diagnostic and Statistical Manual of Mental Disorders – 5th Edition (DSM-5™). IGD and ADHD symptoms, as well as other clinical characteristics, were assessed at baseline and at each subsequent follow-up. Reassessment of the IGD diagnosis was performed annually and used as a dichotomous outcome (IGD vs non-IGD).
There were 128 participants aged 12–42 years with pure-IGD and no other psychiatric disorder (mean (standard deviation, SD] age 22.3 [6.5] years) and 127 participants aged 11–34 years with IGD and comorbid ADHD (mean [SD] age 20.1 [5.7] years). The ADHD-IGD group had significantly higher mean (SD) IGD symptom severity scores (66.6 [9.1]) compared with the pure-IGD group (58.6 [6.9]; p < 0.001) on the Young Internet Addiction Scale (YIAS). The three-year assessment was completed by 62.7% (n=73 with pure-IGD and n=87 with ADHD-IGD) of participants and follow-up rates did not differ significantly between the two groups at Years 1, 2 and 3.
Recovery and recurrence of IGD
The ADHD-IGD group showed a lower probability of recovery compared with the pure-IGD group (p < 0.001), even after adjusting for age at baseline and IQ (hazard ratio, 0.26; 95% confidence interval [CI], 0.17 to 0.40; p < 0.001). Additionally, the ADHD-IGD group had a higher probability of recurrence over the follow-up period (p = 0.006) and had a significantly higher odds of recurrence within one year compared with the pure-IGD group (odds ratio, 4.98; 95% CI, 1.19 to 29.37; p = 0.03).
Changes over time in IGD symptoms and relationship between IGD and ADHD symptoms
Linear mixed modelling determined that IGD symptoms significantly improved over time for both groups (β, –0.27; 95% CI, –0.34 to –0.21; p < 0.001). The ADHD-IGD group showed consistently higher severity of IGD symptoms than the pure-IGD group during follow-up periods. The group aged 20–29 years showed higher severity of IGD symptoms (β, 0.23; 95% CI, 0.06 to 0.41; p = 0.007) compared with other age groups; the group aged ≥30 years showed greater improvement in IGD symptoms than those in other age groups (β, –0.26; 95% CI, –0.37 to 0.15; p < 0.001 for group interaction). Higher anxiety symptoms were associated with increased IGD symptom severity (β, 0.09; 95% CI, 0.04 to 0.15) and better family environments were associated with decreased IGD symptom severity (β, –0.30; 95% CI, –0.38 to –0.27). Furthermore, participants who received psychiatric intervention during the previous year showed significantly lower IGD symptom severity (β, –0.22; 95% CI, –0.30 to –0.13; p < 0.001). Multivariate mixed-effects modelling indicated the strong positive relationships between the person-specific baseline values of IGD symptom severity and ADHD symptom severity, according to the YIAS and the ADHD rating scale (r1=0.75, p < 0.001) and the person-specific rates of change for the symptom severity scores (rs=0.75, p < 0.001).
There were several limitations to this study. First, half of the participants in the pure-IGD group dropped out at Year 3 and the follow-up rates were significantly lower than those in the ADHD-IGD group. Second, the annual follow-up schedule could have impaired the exact dating of the time of recovery and recurrence. Third, caution is advised when generalising the findings of the study using IGD criteria in DSM-5™, to gaming disorder defined by International Classification of Diseases – 11th Revision (ICD-11), as ICD-11 criteria may be stricter compared with criteria in DSM-5™ (Jo et al, 2019). Finally, the study was a naturalistic follow-up; therefore, naturally occurring changes in treatment, gaming and society may have impacted the results.
The authors concluded that the results indicate that ADHD comorbidity in individuals with IGD is associated with a poor longitudinal course of IGD. Additionally, the severity and longitudinal changes in ADHD symptoms were associated with those of IGD symptoms over time. The authors emphasised that evaluation and treatment of ADHD symptoms and the family environment of those with IGD are important for the improvement of IGD prognosis. Finally, the authors suggested that further longitudinal studies are warranted to evaluate the pathological mechanism of the relationship between ADHD and IGD.
Read more about ADHD and internet gaming disorder severity here
*Exclusion criteria included: IQ <70, a history of psychotic disorders, current psychotropic medication usage and neurological or medical diseases.
Jo YS, Bhang SY, Choi JS, et al. Clinical characteristics of diagnosis for internet gaming disorder: comparison of DSM-5 IGD and ICD-11 GD diagnosis. J Clin Med 2019; 8: 945
Lee J, Bae S, Kim BN, et al. Impact of attention-deficit/hyperactivity disorder comorbidity on longitudinal course in Internet gaming disorder: a 3-year clinical cohort study. J Child Psychol Psychiatry 2021; Epub ahead of print.